import java.io.*;
import java.net.*;

public class UDPServer 
{
   public static void main(String args[]) throws Exception
      {
         DatagramSocket serverSocket = new
                              DatagramSocket(9876);
            byte[] receiveData = new byte[1024];
            byte[] sendData = new byte[1024];
            while(true)
               {
                  DatagramPacket receivePacket =
                     new DatagramPacket(receiveData, 
                              receiveData.length);
                  serverSocket.receive(receivePacket);
                  String sentence = new String(
                              receivePacket.getData());
                  InetAddress IPAddress =
                              receivePacket.getAddress();
                  int port = receivePacket.getPort();
                  String capitalizedSentence = 
                              sentence.toUpperCase();
                  sendData = capitalizedSentence.
                              getBytes();
                  DatagramPacket sendPacket =
                  new DatagramPacket(sendData,
                           sendData.length, 
                              IPAddress, port);
                  serverSocket.send(sendPacket);
               }
      }
}



